docs: def load_credentials(self, profile):
          """
          Loads crentials for a given profile. Profiles are stored in
          ~/.db.py_s3_{profile_name} and are a base64 encoded JSON file. This is
          not to say this a secure way to store sensitive data, but it will
          probably stop your little sister from spinning up EC2 instances.
  
          Parameters
          ----------
          profile: str
              identifier/name for your database (i.e. "dev", "prod")
          """
          f = profile_path(S3_PROFILE_ID, profile)
          if os.path.exists(f):
              creds = load_profile(f)
              if 'access_key' not in creds:
                  raise Exception("`access_key` not found in s3 profile '{0}'".format(profile))
              self.access_key = creds['access_key']
              if 'access_key' not in creds:
                  raise Exception("`secret_key` not found in s3 profile '{0}'".format(profile))
              self.secret_key = creds['secret_key']